Device for conveying a motion picture film

ABSTRACT

A device for conveying a motion picture film has at least one uniformly distributed row of perforations. An unwinding toothed reel, which continuously unwinds the motion picture film from a film supply reel, a winding toothed reel that continuously winds the motion picture film onto a film winding reel, and a film feeding mechanism, which intermittently conveys the motion picture film, engage inside said perforations. In order to switch the film conveyance from three to four perforation holes per film frame, the rotational speed of the film conveying motor connected to the winding toothed reel and to the unwinding toothed reel, is increased by 4:3, whereas the multiplication of the film feeding mechanism, of the movement gearing or of a movement gearing element can be altered by three or four perforation holes per film frame in order to adapt to the conveyance of the motion picture film.

CROSS-REFERENCE TO A RELATED APPLICATION

This application is a National Phase patent application of InternationalApplication Number PCT/DE2004/001281, filed on Jun. 17, 2004, whichclaims priority of German Patent Application Number 103 27 771.4, filedon Jun. 17, 2003.

BACKGROUND

The invention relates to a device for conveying a motion picture film.

From German Patent Application No. DE 44 18 471 A1 a motion picture filmrecording camera is known for the exposure and intermittent conveyanceof a motion picture film which is perforated along one or both sides.The unexposed motion picture film mounted in a film cassette connectedto the camera housing of the motion picture film recording camera entersthrough an opening into the camera housing of the motion picture filmrecording camera and then leaves through this opening as exposed film.The feed of the motion picture film consists of one or more filmconveying toothed reels which move the motion picture film continuouslywhilst a film feed mechanism moves the motion picture filmintermittently past a picture window where it is covered in thetransport phase through a rotating aperture and released for exposureduring the exposure phase. In order to balance the continuous filmmovement and intermittent film movement film loops are formed on eitherside of the picture window.

The rotating aperture consists of an aperture disc which is eitherdriven by an aperture motor which is coupled electrically to the filmconveying or camera motor of the film drive so that the speeds of theaperture motor and of the camera motor run synchronously, or a directmechanical coupling is provided where the rotating aperture is coupledto the camera motor through a film conveying gear.

The film feeding mechanism contains a film guide and a plunge gripperswitch mechanism with a transport gripper which is moved by a grippergearing so that its at least one transport gripper point during theintermittent conveyance of the motion picture film describes a closedcrank loop where the transport gripper point first projects into thefilm perforation, implements the film transport step, moves back out ofthe film perforation and returns to its starting position. At thereversing points of the crank loop of the transport gripper the lockinggripper point of a locking gripper correlated with the movement of thetransport gripper and describing an oscillation movement engages in thefilm perforation, undertakes any possible correction of the alignment ofthe motion picture film in the film plane and secures the pictureposition of the motion picture film during the exposure of the filmframe. After exposure of the film frame of the motion picture film thelocking gripper point is again withdrawn so that the motion picture filmis released for a further film transport step by the transport gripper.

In order to enable a greater exposure clearance during exposure of themotion picture film or a greater brightness performance during playbackof the motion picture film the gripper gear contains two gear shaftsmoved in the same rotational direction of which one gear shaft hasn-times the angular speed compared with the other gear shaft and thelight sector of the aperture disc is either variable proportional to theangular speed or the diameter of the aperture disc is selectableinversely proportional to the angular speed and the centre point of theaperture is shifted relative to the picture window with decreasingdiameter of the aperture disc.

It is known to move the motion picture film for exposure or projectionof a film image depending on the desired image format either by three orfour perforation holes of the single or double-sided film perforationduring one film transport step and thus through different lateralconditions of the image formats and with film transport steps by threeperforation holes to obtain a 25% greater utilisation of the filmmaterial used.

From German Patent Publication No. DE 690 24 048 T2 a toothed reelstructural assembly is known for adapting a film projector to filmtransport steps by three or four perforation holes per film framewherein the toothed reel connected to a drive shaft consists either of acylindrical inner sleeve with teeth engaging in the film perforation orof a cylindrical outer sleeve likewise with teeth engaging in the filmperforation and insertable on the cylindrical inner sleeve. With thesame speed of drive shaft and the same toothed spacing but differentdiameter of the inner sleeve and outer sleeve four/three times as muchmotion picture film is transported with the outer sleeve than when usingthe inner sleeve with the outer sleeve removed so that the outer sleeveis designed suitable for film transport steps by four perforation holesper film frame and the inner sleeve for film transport steps about threeperforation holes per film frame.

The known toothed reel structural assembly can indeed be used in a filmprojector which is equipped solely with toothed reels for the continuousand for the intermittent film transport with selectively three or fourperforation holes per film picture. It cannot however be used for thefollowing reasons, or at least not without limitations, for the filmtransport by selectively three or four perforation holes per filmpicture in a motion picture film recording camera, as in the motionpicture film recording camera known from German Patent Application No.DE 44 18 471 A1 with film toothed reels for the continuous filmconveyance and with a gripper feed mechanism for intermittent filmconveyance.

With a film conveyance step of four perforation holes per film frame thetransport gripper conveys the motion picture film during one revolutionof the camera motor by four perforation holes each time whereby theunwinding toothed reel drawing the motion picture film out from the filmcassette and the winding toothed reel conveying the motion picture filmagain into the film cassette execute one revolution about four toothedspacings each time. If the toothed reels each have 16 teeth then theyconsequently turn one quarter of the drive shaft of the camera motordriving the gripper feed mechanism. Compared to this the transportgripper with a film conveyance step about three perforation holes perfilm frame conveys the motion picture film three perforation holes foreach revolution of the camera motor. To maintain constant film loops tocompensate for the intermittent and continuous film conveyances it isnecessary therefore in the case of a camera motor driving both thegripper feed mechanism and the toothed reels to change the translationratio for driving the toothed reels so that these only turn by threeteeth during one revolution of the gripper drive shaft and draw off acorresponding film length from the film cassette and feed it into thefilm cassette.

A use of the toothed reel structural assembly known from German PatentPublication No. DE 690 24 048 T2 in a motion picture film recordingcamera with a gripper feed mechanism would therefore make it necessaryto re-equip the winding toothed reel and unwinding toothed reel oralternatively to replace the film transport gear for driving the toothedreels or by replacing gear elements such as belts and gear wheels toadapt it to the changed speed of the camera motor. For this however itwould be necessary to dismantle the entire inner camera of the motionpicture film recording camera or parts thereof, more particularly thecamera electronics which involves considerable expense and additionalcosts.

The object of the present invention is therefore to adapt the devicementioned at the beginning to a film conveyance of three or fourperforation holes per film frame without exchanging the film conveyancegearing or the winding and unwinding toothed reels or changing thegeometry of the winding and unwinding toothed reels.

SUMMARY OF THE INVENTION

The solution according to the invention enables a film conveyance in amotion picture film recording camera with a gripper feed mechanism bythree or four perforation holes per film frame without the need toexchange the film conveyance gearing or the winding and unwindingtoothed reels or to change the geometry of the winding and unwindingtoothed reels.

The solution according to the invention is based on the knowledge thatto adapt a motion picture film recording camera with a gripper feedmechanism to an alternative film conveyance of three or four perforationholes per film transport step it is for structural design reasons mucheasier and technically more elegant only to exchange the gripper feedmechanism designed as a gripper block or the gripper gearing and toleave the film conveyance gearing including the camera motor and thewinding and unwinding toothed reels unchanged, and instead to provide anelectrical switch-over for the speed of the camera motor driving thegripper feed mechanism and the toothed reels or of the winding motorwhich drives the toothed reels and is connected electrically orelectronically to the camera motor. Whereas the camera motor or thewinding motor during a film conveyance of four perforation holes perfilm frame rotates at full speed which corresponds to the speed of therotating aperture so that the winding and unwinding toothed reels moveon by four perforation holes per revolution of the drive shaft of thecamera motor, the camera motor or the winding motor turn with a filmconveyance of three perforation holes per film frame only with threequarters of the speed of the rotating aperture so that the winding andunwinding toothed reels likewise move on by three perforation holes perrevolution of the drive shaft of the camera motor. Since the transportgripper of the gripper feed mechanism also with a film conveyance bythree perforation holes per film transport step must make one completerevolution of its crank loop when the rotating aperture makes onecomplete revolution, the gripper gearing must execute a 4:3 translationso that the transport gripper executes a complete crank loop again whenthe rotating aperture makes one complete revolution.

Consequently the device according to the invention is fitted forconveying a motion picture film which has at least one uniformly spacedrow of perforations into which engages an unwinding toothed reelunwinding the motion picture film continuously from a film supply spool,a winding toothed reel winding the motion picture film continuously uponto a film winding spool, as well as a gripper feed mechanism whichconveys the motion picture film along intermittently. To convey themotion picture film along by three or four perforation holes per filmtransport stage the winding toothed reel and unwinding toothed reel movethe motion picture film by three or four perforation holes per each filmtransport step whilst different gripper feed mechanisms are provided andcan be used to convey the motion picture film by three or fourperforation holes per film transport step.

Whereas to convey the film by three or four perforation holes for eachfilm transport step the winding and unwinding toothed reels are drivenat different angular speeds, i.e. at different speeds for the windingmotor which drives the winding and unwinding toothed reel, the geometryand/or kinematics of the gripper feed mechanism is adapted to therelevant film conveyance of three or four perforation holes per filmtransport step.

Preferably different gripper feed mechanisms for the film transport ofthree or four perforation holes per film transport step are provided asa so-called “gripper block” and are exchanged for example through a sidecamera door into the camera housing when changing the film transportstep without having to undertake any further action in the cameramechanism.

Since there are different drive forms and drive combinations for drivingthe gripper feed mechanism, the winding and unwinding toothed reels aswell as the rotational aperture, the solution according to the inventionalso allows different variations in design.

In a first variation of the invention in which a camera motor drivesboth the gripper feed mechanism and also the winding and unwindingtoothed reels, the speed of the camera motor is changed for theconveyance of the motion picture film by three or four perforation holesper film transport step and a gripper feed mechanism is used which isadapted in its kinematics to the film transport by three or fourperforation holes per film transport step.

In a second variation in which the camera motor drives the gripper feedmechanism whilst a winding motor drives the winding and unwindingtoothed reel with which it is mounted normally together in the filmcassette, only the speed of the winding motor is changed to the filmtransport by three or four perforation holes per film transport stepwhilst the speed of the camera motor remains unchanged and the gripperfeed mechanism adapted to the film transport by three or fourperforation holes per film transport is used as a gripper block in thecamera mechanism.

Depending on the type of variation either the speed of the camera motordriving both the gripper feed mechanism and the winding and unwindingtoothed reel or the speed of the winding motor driving the winding andunwinding toothed reel, and of the winding motors driving the windingtoothed reel and unwinding toothed reel are switched over so that thewinding toothed reel and unwinding toothed reel move the motion picturefilm with three or four perforation holes per film transport step.

The solution according to the invention is particularly suitable for agripper feed mechanism with a gripper gearing and at least one transportgripper with transport gripper tips engaging in the perforation holes ofthe motion picture film and executing for film conveyance an oblong pathwhich is closed per se in which they project into the perforation holes,move the motion picture film further on by three or four perforationholes each time and then move out of the perforation holes to return totheir original position and whose translation ratio corresponds to afilm conveyance by three or four perforation holes per film frame.

In this embodiment of the film feed mechanism as gripper gearing it ispossible to undertake the change in the translation ratio of the grippergearing for a film conveyance by three or four perforation holes perfilm frame by switching over the gripper gearing.

The connection of the first or second film feed mechanism is preferablycarried out through a coupling to the film conveying motor or to a filmtransport gearing driven by the film conveying motor.

The connection of the relevant film feed mechanism to the film conveyingmotor or to the film transport gearing through a coupling makes iteasier to exchange it for the alternative film conveyance by three orfour perforation holes per film frame without having to make any greatintervention into the film feed mechanism or into the mechanics of themotion picture film recording camera. More particularly the exchange canbe made without dismantling the control electronics of the motionpicture film recording camera and an existing coupling can be used tofold back the gripper feed mechanism when threading a motion picturefilm into the motion picture film recording camera.

In addition but not absolutely necessary the gripper feed mechanism canhave a locking gripper coupled to the path of movement of the at leastone transport gripper to project into a perforation hole of the motionpicture film during the picture position of the film frames.

Basically the solution according to the invention is suitable both for amotion picture film recording camera and for a projector whereby theadvantages of the solution according to the invention are particularlyapparent when a gripper feed mechanism is connected to the filmtransport gear for driving the winding and unwinding toothed reel and aconstant speed has to take place with a rotating aperture when adaptedto the film conveyance by three or four perforation holes per film framewhich is driven either by an aperture motor which is coupledelectrically to the film conveying motor or which is connectedmechanically through gearing to the film feed mechanism and is likewisedriven by the film conveying motor.

A preferred embodiment of the invention relates to a motion picture filmrecording camera with a camera housing in which a rotating circularsector shape aperture disc is mounted in the recording beam path andcovers the picture window during a film transport step of the film feedmechanism and releases the recording beam path to expose the film frameduring the picture position of the motion picture film and a cameraelectronics connected at least in part to the camera housing, wherebythe gripper gearing of the film feed mechanism contains a drive shaftconnectable with the film conveying motor or film transport gearing witha first gripper toothed wheel whose diameter determines the filmtransport by three or four perforation holes per film picture, atransport gripper bracket whose one end supports the transport grippertip or transport gripper tips and whose other end has a transportgripper joint which is connected to a second gripper gear wheeldetermining the gripper stroke of the transport gripper, and in themiddle section of which is a crank joint which is connected to a thirdgripper gear wheel determining the movement of the transport gripperperpendicular to the plane of the motion picture film, and a toothedbelt connecting the gripper gear wheels together.

In order to adapt the gripper gearing to the film conveyance by three orfour perforation holes per film frame either the first gear wheel can beexchanged and in a first embodiment be set with a diameter correspondingto the film conveyance by three perforation holes per film frame and ina second embodiment with a diameter corresponding to the film conveyanceby four perforation holes per film frame or the first gear wheel isdivided in the axial direction and has a first gear wheel part with afirst diameter corresponding to the film conveyance by three perforationholes per film frame and a second gear wheel part with a second diametercorresponding to the film conveyance by four perforation holes per filmframe whereby the tooth spacings of the two gear wheel parts coincidewith each other.

The solution according to the invention is however as an alternative tothe gripper feed mechanism also suitable for a film feed mechanism whichcontains a film conveyance toothed reel which is according to theinvention provided with a diameter adapted to the film conveyance bythree or four perforation holes per film frame. Unlike in the prior art,when using the solution according to the invention it is therefore notnecessary to also reset or modify the winding and unwinding toothed reelfor a film conveyance by three or four perforation holes per film framebut only to carry out a speed adaption of the film conveying motor andto insert the film conveying toothed reel required into the film feedmechanism.

Instead of inserting the relevant film conveying toothed reel which isrequired into the film feed mechanism as an alternative it is possibleto provide the relevant film feed mechanism with a film conveyingtoothed reel for conveying the motion picture film by three or fourperforation holes per film frame whereby the film conveying toothed reelof the one film feed mechanism has a diameter adapted to the filmconveyance by three perforation holes per film frame and the other filmfeed mechanism has a film conveying toothed reel with a diameter adaptedto the film conveyance by four perforation holes per film frame.

BRIEF DESCRIPTION OF THE DRAWINGS

The idea on which the invention is based will now be described infurther detail with reference to the embodiment illustrated in thedrawings.

FIG. 1 is a side view of a motion picture film recording camera with adevice for conveying a motion picture film with a winding and unwindingtoothed reel and a gripper feed mechanism.

FIG. 2 is a diagrammatic perspective view of the film conveying deviceaccording to FIG. 1.

FIG. 3 a shows a first block circuit diagram for explaining the filmconveyance with three and four perforation holes respectively per filmtransport step with a camera motor driving the gripper feed mechanismand the winding and unwinding toothed reels, and an aperture motorcoupled electronically to the camera motor for driving the rotatingaperture.

FIG. 3 b shows a second block circuit diagram for explaining the filmconveyance with three and four perforation holes respectively per filmtransport step with a camera motor driving the gripper feed mechanismand the winding and unwinding toothed reels, and an aperture motorcoupled electronically to the camera motor for driving the rotatingaperture.

FIG. 4 a shows a first block circuit diagram for explaining the filmconveyance with three or four perforation holes per film transport stepwith a camera motor driving the gripper feed mechanism and the rotatingaperture, and one or two winding motors driving the winding andunwinding toothed reels.

FIG. 4 b shows a second block circuit diagram for explaining the filmconveyance with three or four perforation holes per film transport stepwith a camera motor driving the gripper feed mechanism and the rotatingaperture, and one or two winding motors driving the winding andunwinding toothed reels.

FIG. 5 a shows a first block circuit diagram for explaining the filmconveyance with three or four perforation holes per film transport stepwith camera motor, winding motor and aperture motor coupled togetherelectronically.

FIG. 5 b shows a second block circuit diagram for explaining the filmconveyance with three or four perforation holes per film transport stepwith camera motor, winding motor and aperture motor coupled togetherelectronically.

DETAILED DESCRIPTION

FIG. 1 shows a motion picture film recording camera with a camerahousing 1, a viewfinder eyepiece 11, a camera lens 12 and a cameramagazine 13 attached to the camera housing 1 and containing a filmsupply spool with unexposed motion picture film 10 and a film windingspool with the motion picture film which has been exposed by the motionpicture film recording camera. The camera housing 1 which is shownpartially opened contains a winding toothed reel 15 and an unwindingtoothed reel 16 which unwinds the motion picture film 10 continuouslyfrom the film supply spool of the camera magazine 13 and winds itcontinuously onto the film winding spool of the camera magazine 13.

A film feed mechanism 2 (also referred to as a “gripper feed mechanism”)driven by a camera motor (not shown in further detail) moves the motionpicture film 10 intermittently past a film-gate 90 of a film guide 9whereby the motion picture film 10 in the transport phase of the gripperfeed mechanism is covered by a sector-shaped aperture disc of a rotatingshutter 7 and is released through a sector-shaped cut-out section of theaperture disc of the rotating shutter 7 in order to expose a film image.The sector-shaped aperture disc of the rotating shutter 7 is driven byan mirror shutter motor 6 which is electrically coupled to the cameramotor of the film feed mechanism 2 so that the speeds of the two motorsrun synchronously. Alternatively a mechanical coupling can be providedwhere the rotating shutter 7 is connected together with the film feedmechanism 2 through a film conveyance gearing to the camera motor.

In order to balance the continuous transport movement of the motionpicture film 10 generated by the winding and unwinding toothed reels 15,16 with the intermittent transport movement created through the gripperfeed mechanism, film loops are formed on either side of the film-gate90.

The film feed mechanism 2 serves to transport the motion picture film 10and has for this purpose two pull-down claws 21, 22 (also referred to as“transport grippers”) and where applicable to secure the pictureposition two registration pins 23, 24 associated with the pull-downclaws 21, 22 to project into the perforation holes of the filmperforations of the motion picture film 10. Furthermore the film feedmechanism 2 contains a movement gearing 3 with a drive shaft which isconnected to the film transport gearing or to the camera motor. Thepull-down claws 21, 22 and registration pins 23, 24 are formed as plungegrippers and have at their ends facing the motion picture film 10transport gripper tips and locking gripper tips respectively whichproject alternately into the perforation holes of the film perforationsof the motion picture film 10.

The pull-down claws 21, 22 execute with each film transport step ahorizontal and vertical movement whereby the transport gripper tips orpull-down claw tips run through an elongated closed curve and at one endof the curve project into the perforation holes of the film perforationswhich they then leave at the other end of the curve so that the distancebetween the two reversal points determines the stroke length of thepull-down claws 21, 22 and their transport gripper tips and thus a filmtransport step.

Through the mechanical coupling of the pull-down claws 21, 22 and theregistration pins 23, 24 the latter are located during a film transportstep in which the motion picture film 10 is moved on farther by one filmframe, outside of the film plane of the motion picture film 10 whilstthe transport gripper tips have projected into the film perforations andmove the motion picture film 10 corresponding to the predeterminedstroke length between the upper and lower reversal points.

At the end of a film transport step the transport gripper tips leave thefilm perforations, the locking gripper tips project into the filmperforation hole of the film perforations which aligns with the lockinggripper tips and thereby guarantees a fixed picture position of themotion picture film 10 of which the part which is to be exposed ispositioned in front of the film-gate 90 which is released duringexposure of the motion picture film 10 through the rotating shutter 7which is mounted in front of the film-gate 90.

The film guide 9 consists of two side film supports on which the edge ofthe motion picture film 10 slides along with the film perforations onboth sides parallel to the side edges of the motion picture film 10.

The intermittent and continuous film conveyance, the arrangement of thewinding and unwinding toothed reels as well as the drive of the rotatingaperture can be different depending on the design of motion picture filmrecording camera.

Apart from a mechanical coupling of the rotating aperture with thecamera motor driving the gripper feed mechanism the winding andunwinding toothed reels can also be coupled mechanically to the cameramotor. As an alternative to this an arrangement is also possible of thewinding and unwinding toothed reel in the film cassette and its drive bya winding motor coupled electronically to the camera motor for thewinding and unwinding toothed reel or two winding motors coupledelectronically to the camera motor for the winding toothed reel orunwinding toothed reel. Furthermore the separate drive of the rotatingaperture already mentioned above by an aperture motor which is likewisecoupled electronically to the camera motor is also possible.

The film conveying device illustrated in a perspective view in FIG. 2has corresponding to the embodiment of a motion picture film recordingcamera illustrated in FIG. 1 a camera motor 4 which drives both thewinding toothed reel 15 and the unwinding toothed reel 16 as well as thefilm feed mechanism 2 through a film transport gearing 8. The filmtransport gearing 8 contains a first film transport gear wheel 81connected to the motor shaft of the camera motor 4 and through a filmconveyance toothed belt 80 to a second film transport gear wheel 82 anda third film transport gear wheel 83 which drives the gripper driveshaft 30 of the movement gearing 3.

The second film transport gear wheel 82 is coupled to a further filmtransport gear wheel 84 of smaller diameter which is connected through asecond film transport toothed belt 85 to a first film winding gear wheel86 which drives the winding toothed reel 15 and unwinding toothed reel16 through a second film winding gear wheel 87 as well as a connectionwhich is not shown in further detail.

The film feed mechanism 2 is connected to the film guide 9 which hascurved film skids for guiding the motion picture film and for itsexposure on the film-gate 90. The film feed mechanism 2 contains amovement gearing 3, the two pull-down claws 21, 22 engaging in each oneof the two rows of perforations of the motion picture film, as well asin this embodiment two registration pins 23, 24 which project in eachone of the two rows of perforations of the motion picture film for thealignment and securing of the picture position during the film exposureof the motion picture film.

The pull-down claws 21, 22 contain a transport gripper bracket 21 a, 22a which has at its one end a transport gripper joint 21 b, 22 b and atits other end three transport gripper tips 21 c, 22 c which for the filmconveyance describe an elongated closed crank loop where they firstproject into three adjoining perforation holes of the film perforations,execute a film transport step, leave the film perforation again andreturn to their original position. The transport gripper joint therebydetermines the movement of the transport gripper tips perpendicular tothe plane of the motion picture film and a crank joint mounted betweenthe transport gripper joint and the transport gripper tips determinesthe transport stroke of the transport gripper tips in the conveyancedirection of the motion picture film.

The registration pins 23, 24 are connected to the movement gearing 3through a control element (not shown in further detail) so that theyimplement an oscillating movement perpendicular to the film plane andthereby each project with their locking gripper tips into a perforationhole of the film perforations in alternating play with the transportgripper tips.

The movement gearing 3 has the gripper drive shaft 30 which is connectedto the third film transport gear wheel 83 of the film transport gearing8 and which supports a first claw gear wheel 31 which is connectedthrough a claw toothed belt 34 to a second claw gear wheel 32 which iscoupled to the transport gripper joints and thus determines the movementof the pull-down claws 21, 22 perpendicular to the plane of the motionpicture film, as well as is connected to a third claw gear wheel 33which is coupled to the crank joint and consequently determines thetransport stroke of the transport gripper tips in the transportdirection of the motion picture film.

The gripper drive shaft 30 can be made divided and have a coupling 14which is designed for example corresponding to the coupling known fromGerman Patent Application No. DE 42 05 411 A1. Through the arrangementof the coupling 14 or through a gripper drive shaft 30 connectable in adifferent way to the third film transport gear wheel 83 of the filmtransport gearing 8 the film feed mechanism 2 can be simply exchangedfor a film feed mechanism 2′ and thus with an unchanged arrangement ofthe camera motor 4 of the film transport gearing 8 and winding andunwinding toothed reels 15,16 can be adapted to a film conveyance byeither three or four perforation holes per film frame or film transportstep.

Apart from a complete exchange of the film feed mechanism 2 designed asa gripper block for a film feed mechanism 2′ a part exchange of themovement gearing 3 for a movement gearing 3′ with the pull-down claws21, 22 and registration pins 23, 24 by retaining the film guide 9 isalso possible.

If in place of the film feed mechanism 2 with transport grippersillustrated in FIG. 2 a film transport toothed reel is used then thiscan either be driven through a gearing corresponding to the movementgearing 3 with a different translation ratio or a film conveyancetoothed reel of a smaller diameter is used for a film conveyance bythree perforation holes per film frame or a film conveyance toothed reelof larger diameter is used for a film conveyance by four perforationholes per film frame.

Different embodiments of the solution according to the invention areshown as block circuit diagrams in FIGS. 3 a, 3 b, 4 a, 4 b and 5 a, 5b.

In a first variation FIGS. 3 a and 3 b show a block circuit diagram ofthe mechanically coupled drive of the film feed mechanism 2 illustratedin perspective view in FIG. 2 and of the winding and unwinding toothedreels 15, 16 by the camera motor 4, and the drive which is separatedtherefrom of the rotating shutter 7 by an mirror shutter motor 6 coupledelectronically to the camera motor 4.

With the film conveyance of the motion picture film with fourperforation holes per film transport step shown diagrammatically in FIG.3 a the camera motor 4 drives the film feed mechanism 2 which is adaptedto the film transport by four perforation holes per film transport stepand the winding and unwinding toothed reels 15, 16 with the speed n_(k1)so that the winding and unwinding toothed reels 15, 16 rotate the motionpicture film by four perforation holes per film transport step duringone revolution of the gripper feed mechanism. The speed n_(B) of themirror shutter motor 6 corresponds to the speed n_(K1) of the cameramotor taking into account the translation up or down of the filmtransport gearing 8 connected to the camera motor 4 according to FIG. 2.

With a film conveyance illustrated diagrammatically in FIG. 3 b by threeperforation holes per film transport step the camera motor 4 drives thefilm feed mechanism 2′ which is adapted to the film conveyance by threeperforation holes per film transport step and the winding and unwindingtoothed reels 15, 16 with a speed n_(K2) which amounts to ¾ of the speedn_(K1) for the film transport by three perforation holes per filmtransport step. The winding and unwinding toothed reels 15, 16 arethereby only turned per revolution by three perforation holes of themotion picture film whilst the film feed mechanism 2′ executes onecomplete revolution when the rotating shutter 7 likewise completes onecomplete revolution. The film feed mechanism 2′ is translated with 4:3compared with the film feed mechanism 2 and consequently leads to acomplete revolution with a complete revolution of the rotating shutter 7which is driven by the mirror shutter motor 6 which is coupledelectronically to the camera motor 4.

FIGS. 4 a and 4 b show in a block circuit diagram a variation in whichthe camera motor 4 drives both the film feed mechanism 2, 2′ and alsothe rotating shutter 7 whilst a film winding motor driving the windingand unwinding toothed reels 15, 16 and winding motors each driving thewinding toothed reel 15 and the unwinding toothed reel 16 is/are coupledelectronically to the camera motor 4.

In the embodiment according to FIG. 4 a with a film transport by fourperforation holes per film transport step the camera motor 4 is operatedwith a speed n_(K) when using a film feed mechanism 2 adapted to thefilm conveyance by four perforation holes per film transport step,whilst the film winding motor 5 drives with the speed n_(w1) the windingand unwinding toothed reels 15, 16 which convey the motion picture filmwith each film transport step by four perforation holes.

With a film transport diagrammatically illustrated in FIG. 4 b by threeperforation holes per film transport step the camera motor 4 is operatedwith the same speed n_(K) for driving the film feed mechanism 2′ adaptedto the film transport by three perforation holes per film transportstep, and the rotating shutter 7. On the other hand the film windingmotor 5 rotates at a speed n_(W2) which amounts to ¾ of the speed n_(W1)so that the winding and unwinding toothed reel 15, 16 are turned on bythree perforation holes per film transport step whilst the film feedmechanism 2′ and the rotating shutter 7 execute one complete revolution.

FIGS. 5 a and 5 b show a block circuit diagram of one embodiment eachwith their own drive for the film feed mechanism 2, 2′, the winding andunwinding toothed reel 15, 16 and the rotating shutter 7 by a cameramotor 4, a film winding motor 5 and an mirror shutter motor 6 which arecoupled electronically together.

With a film transport step illustrated diagrammatically in FIG. 5 a offour perforation holes the camera motor is operated with a speed n_(k)and drives a film feed mechanism 2 which is adapted to the filmtransport step of four perforation holes. The film winding motor 5drives the winding and unwinding toothed reel 15,16 at a speed n_(W1) sothat these move the motion picture film on further with each filmtransport step by four perforation holes. The mirror shutter motor 6 isoperated at a speed n_(B) at which the rotating shutter 7 makes acomplete revolution when the film feed mechanism 2 likewise has runthrough a complete crank loop and the winding and unwinding toothedreels 15, 16 have move the motion picture film on by four perforationholes.

With a film transport step likewise illustrated diagrammatically in FIG.5 b of three perforation holes the camera motor 4 is likewise operatedat a speed n_(K) and drives a film feed mechanism 2′ which is adapted tothe film transport by three perforation holes per film transport step sothat this runs through a complete crank loop when the rotating shutter 7driven by the mirror shutter motor 6 at a speed n_(B) executes acomplete revolution. On the other hand the film winding motor 5 isoperated with a speed n_(W2) which amounts to ¾ the speed n_(W1) so thatthe winding and unwinding toothed reels 15, 16 move the motion picturefilm 10 on by three perforation holes per film transport step.

1. A film transport device for a motion picture film which has a row ofuniformly spaced perforations which are engaged by an unwinding toothedreel which unwinds the motion picture film continuously from a filmsupply spool, a winding toothed reel which winds up the motion picturefilm continuously onto a winding spool, and a gripper feed mechanismwhich conveys the motion picture film intermittently, said windingtoothed reel and said unwinding toothed reel moving the motion picturefilm with one of three and four perforation holes per film transportstep, wherein a film feed mechanism of a plurality of different filmfeed mechanisms is usable for conveying the motion picture film by oneof three and four perforation holes per film transport step.
 2. Thedevice according to claim 1, wherein said different film feed mechanismsare interchangeable.
 3. The device according to claim 1, wherein acamera motor drives the film feed mechanism and the winding andunwinding toothed reels whose speed is changeable for conveying themotion picture film by one of three and four perforation holes per filmtransport step.
 4. The device according to claim 1, wherein a cameramotor drives the film feed mechanism, wherein the winding and unwindingtoothed reels have a variable speed and are connected to at least onefilm winding motor which is coupled electrically or electronically tothe camera motor for conveying the motion picture film by one of threeand four perforation holes per film transport step.
 5. The deviceaccording to claim 3, wherein the speed of one of the camera motor andof the at least one film winding motor is adjustable so that the windingtoothed reel and the unwinding toothed reel move the motion picture filmwith one of three and four perforation holes per film transport step. 6.The device according to claim 1, further comprising a film feedmechanism having a movement gearing and at least one pull-down claw withtransport gripper tips engaging in the perforation holes of the motionpicture film, wherein the transport gripper tips convey the filmexecuting an elongated closed path curve in which said transport grippertips project into the perforation holes, wherein said transport grippertips convey the motion picture film further on one of by three and fourperforation holes each time and then move out of the perforation holesto return to their starting position, and wherein the translation ratioof the movement gearing corresponds to a film conveyance by one of threeand four perforation holes per film transport step.
 7. The deviceaccording to claim 6, wherein the translation ratio of the movementgearing is reversible.
 8. The device according to claim 6, wherein oneof the plurality of film feed mechanisms is connectable through acoupling to one of the camera motor and to a film transport gearingdriven by the camera motor.
 9. The device according to claim 6, whereinthe movement gearing contains a drive shaft connectable to one of thecamera motor and film transport gearing and comprises: a first claw gearwheel whose diameter determines the film conveyance by one of three andfour perforation holes per film transport step; a transport gripperbracket whose one end supports at least one of the transport grippertips and whose other end has a transport gripper joint which isconnected to a second claw gear wheel for the movement of the transportgripper tips perpendicular to a plane of the motion picture films,wherein a center section of said bracket there is a crank joint which isconnected to a third claw gear wheel determining the transport stroke ofthe transport gripper tips; and a toothed belt connecting the claw gearwheels together, wherein the first claw gear wheel is exchangeable andin a first embodiment has a diameter corresponding to the film transportby three perforation holes per film transport step and in a secondembodiment has a diameter corresponding to the film transport by fourperforation holes per film transport step.
 10. The device according toclaim 1, wherein the film feed mechanism contains a film transporttoothed reel with a diameter adapted to allow for the film conveyance byone of three and four perforation holes per film transport step.
 11. Thedevice according to claim 1, wherein a rotating circular sector shapedshutter disc is mounted in the recording beam path of a motion picturefilm recording camera and is coupled to the conveyance of the motionpicture film and is driven independently of a film transport step by oneof three and four perforation holes, wherein an aperture disc covers afilm-gate during a film transport step of the film feed mechanism andreleases the recording beam path for the exposure of a film frame duringthe picture position of the motion picture film.
 12. The deviceaccording to claim 11, wherein the shutter disc and the gripper filmfeed mechanism are connected to the camera motor.
 13. The deviceaccording to claim 11, wherein the shutter disc is connected to thedrive shaft of a mirror shutter motor coupled electronically to thecamera motor and to the winding motor.